Patients seeking medical treatment typically need to be positioned correctly in order to properly receive diagnosis or treatment. One example is in magnetic resonance imaging (MRI) systems that scan portions of a patient's anatomy within a relatively small imaging volume.
One example of an open MRI system is the FONAR 360° system designed by Fonar Corporation. Another example is the OR-360™ (MRI Operating Room), also designed by Fonar Corporation. FONAR 360° systems include magnetic poles that are part of a FONAR 360° scanner. The poles are typically located in the approximate center of a room with one pole protruding from the ceiling and the other pole protruding from the floor. The patient is positioned in the space, or gap, between the two poles and is accessible from virtually any angle. The patient can be placed on his back, stomach or side. A large portion of the MRI system may be located outside the scanning room such that primarily the patient is exposed to the main magnetic field.
FIG. 1 illustrates a portion of an example open MRI system 10. MRI system 10 includes a magnet 11. Magnet 11 includes an upper pole assembly 12 and a lower pole assembly 14 with a gap 16 between the upper and lower pole assemblies 12, 14.
A scanning operation is typically done by positioning a patient bed 17 (which includes a patient) within gap 16 (note arrow X) between upper and lower pole assemblies 12, 14. One type of patient bed 17 includes a frame that is made up a slab 18 and four legs 19 that support slab 19. Each leg 19 typically includes a roller or caster 20 for rolling bed 17 across the floor. The space under slab 18 and between legs 19 is large enough to receive lower pole assembly 14 when patient bed 17 is moved into gap 16.